Mole-Mole Conversions Mass to Mass Calculations

Evaluation/Assessment: Objective: Today I will be able to: Construct mol to mol ratios in order to convert from the mass of a reactant to the mass of a product Evaluation/Assessment: Informal Assessment – Monitoring group interactions as the students complete the mass-mass calculations Formal Assessment – Analyzing student responses to the mass-mass practice and exit ticket Common Core Connection Make sense of problem and persevere in solving them Model with mathematics Use appropriate tools strategically Look for and express regularity in repeated reasoning

Lesson Sequence Evaluate: Warm – Up Evaluate: Review HW Explain: Stoichiometry – Mass-Mass Calculations Elaborate: Mass-Mass Calculations Practice Evaluate: Exit Ticket

Warm - Up Determine the type of representative particle: Br2 CaSO4 (Hint: atom, formula unit, molecule) Br2 CaSO4 NH4Cl Hg P2O5 Al2O3

Objective Today I will be able to: Construct mol to mol ratios in order to convert from the mass of a reactant to the mass of a product

Homework Complete practice worksheet

Agenda Warm-Up Review HW Mass-Mass Calculation Notes Mass-Mass Calculation Practice Exit Ticket

What questions do you have about the practice problems from yesterday? Review HW What questions do you have about the practice problems from yesterday?

Stoichiometry: Mass - Mass Calculations

What is Stoichiometry? The study of quantitative (measurable) relationships that exist in chemical formulas and chemical reactions

Mol-Mol Ratios To convert from mass of a reactant to mass of a product we need to use the mol ratio Mol ratios are determined using the balanced chemical equations Example: 2 H2 + O2  2H2O Example Ratios:

Mol-Mol Problem How many moles of O2 react with 8 moles of H2?

Putting it all together. Mass – Mass Calculation Inquiry

Put it together… Work with a group to solve the problem assigned Use the conversion factors you have learned so far to solve the problem You will present the problem to the class

Mass-Mass Calculation Notes

Mass-Mass Problems You are given the mass of one substance and are asked to find the mass of another substance involved in the same reaction Steps to solving mass-mass problems Mass of given  moles of given  moles of unknown  mass of unknown (Use Mol Road Map)

Mass-Mass Problems Example: 2 Al + Fe2O3  2 Fe + Al2O3 What mass of aluminum was supplied if 2.3 g of aluminum oxide was produced in the reaction? 1 mol Fe2O3 1 mol Al2O3 160 g Fe2O3 1 mol Fe2O3 2.3 g Al2O3 1 1 mol Al2O3 102 g Al2O3 x x x = 3.6 g Fe2O3

Mass-Mass Problems Determine the mass of sodium hydroxide produced when .25 g of Na reacts with water. 2 Na + 2 H2O  2 NaOH + H2 .25 g Na 1 1 mol Na 23 g Na 2 mol NaOH 2 mol Na 40 g NaOH 1 mol NaOH x x x = .43 g NaOH

Stoichiometry Calculations Practice Complete the practice problems at your desk.

Exit Ticket Predict the products of the equation and then balance: Mg + HCl  What is the mol ratio between HCl and MgCl2? If you have 4.0 mol of HCl how many mol of MgCl2 are present?